The present invention relates to a projector-type automobile headlamp employing a projector lamp unit.
Recently, there has come into common use projector-type headlamps using a projector lamp unit in which the output light beam of a light source (bulb) is passed through a projector lens, namely, a convex lens. This arrangement is advantageous due to the greater quantity of output light than in a reflector-type headlamp in which the output light beam of the light source is formed into a parallel light beam using a reflector.
As shown in FIG. 8, in a known headlamp of this general type, a projector lamp unit 3 is arranged in a lamp chamber S defined by a lamp body 1 and a lens 2. In FIG. 8, reference numeral 4 designates a projector lamp cover with a light reflecting surface 4a. The projector lamp cover 4 has an opening 5 into which the projector lens 3a of the projector lamp unit 3 is inserted.
In the case of the above-described conventional headlamp, the light reflecting surface 4a reflects external light, but the projector lens 3a scarcely reflects external light. Hence, when the lamp is turned on, an observer standing in front of the vehicle will see a relatively dark ring in the lamp; that is, the gap 6 between the periphery of the opening 5 and the projector lamp unit 3 appears as a dark ring, as shown by shading in FIG. 9. On the other hand, since the lamp cover 4 is substantially flush with the projector lens 3a, the lamp appears small in depth, or relatively flat, and thus is rather unattractive in appearance.